1. Field of the Invention
The present invention relates to a glass-break preventing film like filter and a plasma display apparatus attached with the same.
2. Description of the Related Art
A conventional plasma display apparatus is, as shown in FIG. 3, formed with a space 320 by a spacer 32 at a visual side of a plasma display plate 31, in which a transparent front plate 33 of a glass plate of around 3 mm thickness is arranged and disposed within a case 34. With this structure arranged with the transparent front plate 33 via the space 320, it is possible to prevent an external shock from directly attacking the plasma display plate 31, and suppress a heat generated in the plasma display plate 31 from transmitting to the transparent front plate 33.
However, a problem is present that an image is reflected in double owing to an air layer formed by the space 320 and refraction of light at a boundary between the plasma display plate 31 and the transparent front plate 33. Further, another problem occurs that the transparent front plate 33 has an around 3 mm thickness so as to stand against the external shock, so that weight is heavy and cost is high.
On the other hand, applicant of this invention already proposed, in Unexamined Japanese Patent Publication No. He. 9-259770, a plasma display apparatus characterized by directly attaching the transparent protective plate at a visual side of the plasma display plate via a heat resistant transparent sheet having a buffering property and an adhesive property. According to this display apparatus, there is no air layer at the visual side, exhibiting an excellent effect avoiding the problem of the double image.
Nevertheless, in the above proposal, since a hard and thick glass plate or an acrylic plate is employed as the transparent protective plate, an operation of attaching this plate to the plasma display plate via the plasma display sheet is not easy. Thus, the glass plate is still involved with problems of weight or cost. In a regard of the impact resistance, the above proposal is not sufficient, and merely judges the impact resistance with impact force (about 0.0294 J) when dropping a steel ball of 3 g weight from a height of 1 mm. For wasting display units, though removing the transparent protective plate for re-cycling, removing is not easy.